1. Field of the Invention
The invention relates generally to a governor and more particularly to a governor for a diesel engine wherein a fuel injection pump is controlled as a function of engine operating parameters. An attachment on the governor of the fuel injection pump limits the distance through which a control rod moves, thereby limiting the corresponding delivery of fuel during starting and/or full load conditions. The attachment may also include a torque control device.
2. Description of the Prior Art
Unexamined West German Patent Application 2650247 is generally directed to the subject matter of the present invention and discloses the adjustment of a control-rod stop of a fuel injection pump as a function of various operating parameters which are continuously recorded and evaluated against predetermined values in order to optimize performance of the internal combustion engine without overloading or risk of damage. In this way, the life of the internal combustion engine can be lengthened and the conventional blocking of the control-rod stop at a predetermined value becomes unnecessary, regardless of the field and mode of application of the internal combustion engine. The control rod stop is an attachment on the governor of a fuel injection pump designed to limit the distance through which the control rod moves, thereby limiting the fuel delivery rate.
However, unexamined West German Patent Application 2650247 requires many control elements to control the fluid which modulates the control rod stop such as accumulators and electromagnetically operating directional control valves. Each of these elements presents sources of error or trouble, such as hysteresis and position errors on the helices or control edges of the fuel injector plunger which accumulate to a total system error so that accurate operation of the governor is not ensured. The control edges are located on spill grooves formed in the fuel injection plungers. The spill grooves are typically of helical form and may be disposed in upper or lower portions of the plunger or both and may be of the same spiral direction or opposite and may be provided on both sides of the plunger.